This invention relates to a piston engine having the features of the preamble of claim 1.
A piston engine has an engine block with several cylinders and is equipped with a fresh gas inlet having several inlet pipes secured on the engine block and allocated to the cylinders. Through this fresh gas inlet, intake air or charging air that is needed for combustion is supplied to the engine. Modern piston engines are equipped with a fuel injection system which has a high-pressure inlet line provided for the cylinders. In such a high-pressure inlet line, the fuel is supplied to the cylinders jointly under a high pressure, and a targeted metering of fuel is accomplished by fuel injectors. Such a common high-pressure inlet line is referred to in general as a xe2x80x9ccommon-railxe2x80x9d injection system.
The high-pressure inlet line is preferably made of metal because of the high fuel pressures. However, plastic is preferred for production of the inlet pipes. Inlet pipes made of plastic are usually mounted on the engine block by means of metal bushings which are welded or fused into a flange section of the inlet pipes to make it possible to screw the inlet pipes onto the engine block. The high-pressure inlet line may be mounted directly on the engine block or on the inlet pipes and thus indirectly on the engine block. It is likewise possible to manufacture the inlet pipes and the high-pressure inlet line in one part of metal, whereby this integral module is then mounted on the engine block by means of a corresponding screw connection.
The present invention is concerned with the problem of designing a piston engine of the type defined in the preamble in such a way as to simplify the mounting of the high-pressure inlet line and the inlet pipes.
This problem is solved according to this invention by a piston engine having the features of claim 1.
This invention is based on the general idea of designing the high-pressure inlet line so that it cooperates with the inlet pipes to the extent that the inlet pipes are mounted on the engine block simultaneously by the mounting of the high-pressure inlet line. Due to this measure, additional fastening means for mounting the inlet pipes on the engine block may be omitted. In particular, it is possible in this way to manufacture the inlet pipes of plastic without having to integrate additional fastening elements made of metal into them. Thus, on the whole this yields an especially economical method of manufacturing the proposed combination of inlet pipes and the high-pressure inlet line.
Additional important features and advantages of the device according to this invention are derived from the subclaims, the drawings and the respective description of the figures on the basis of the drawings.
It is self-evident that the features mentioned above as well as those to be explained below can be used not only in the given combination but also in any other combinations or even alone without going beyond the scope of the present invention.